SHORT-TERM EFFECTS OF UNDERSTORY AND OVERSTORY MANAGEMENT ON BREEDINGBIRDS IN ARKANSAS OAK-HICKORY FORESTS

Relatively little is known about the effects of uneven-aged forest man agement practices on eastern forest birds, despite the fact that such methods are now commonly practiced. In 1993-94, we studied the short-t erm effects of uneven-aged forest management on bird communities in oa k-hickory forests of northwestern Arkansas. We estimated bird abundanc e in mature forests and on managed plots receiving either a heavy cutt ing of understory vegetation (understory treatment) or a combination o f both understory cutting and selective cutting in the forest overstor y (full treatment). Two nesting guilds and 7 of 14 species with adequa te sample size showed significant treatment effects. Ovenbirds (Seiuru s aurocapillus), worm-eating warblers (Helmitheros vermivorus), Acadia n flycatchers (Empidonax virescens), and the understory-nesting guild mere most abundant in mature forest. Indigo buntings (Passerina cyanea ), white-breasted nuthatches (Sitta carolinensis), and eastern wood-pe wees (Contopus virens) were more abundant on full treatment plots. Tuf ted titmice (Baeolophus bicolor) were most abundant on mature forest a nd understory treatment plots. The canopy-nesting guild was most abund ant on understory and full treatment plots. Our results suggest that i f removal of understory vegetation was practiced widely in the Arkansa s Ozarks as part of uneven-aged management, populations of some ground - and shrub-nesting forest interior species of birds could be negative ly affected, whereas a few forest canopy and edge species may respond positively. Future research on this type of uneven-aged management sho uld examine effects of removing varying amounts of understory vegetati on on both forest interior bird populations and forest regeneration.